2 DOSAGE AND ADMINISTRATION
2.1 Dosage in Generalized Anxiety Disorder
The recommended starting oral dosage of XANAX for the acute treatment of patients with GAD is 0.25 mg to 0.5 mg administered three times daily. Depending upon the response, the dosage may be adjusted at intervals of every 3 to 4 days. The maximum recommended dosage is 4 mg daily (in divided doses).
Use the lowest possible effective dose and frequently assess the need for continued treatment [see Warnings and Precautions (5.2)].
2.2 Dosage in Panic Disorder
The recommended starting oral dosage of XANAX for the treatment of PD is 0.5 mg three times daily. Depending on the response, the dosage may be increased at intervals of every 3 to 4 days in increments of no more than 1 mg per day.
Controlled trials of XANAX in the treatment of panic disorder included dosages in the range of 1 mg to 10 mg daily. The mean dosage was approximately 5 mg to 6 mg daily. Occasional patients required as much as 10 mg per day.
For patients receiving doses greater than 4 mg per day, periodic reassessment and consideration of dosage reduction is advised. In a controlled postmarketing dose-response study, patients treated with doses of XANAX greater than 4 mg per day for 3 months were able to taper to 50% of their total maintenance dose without apparent loss of clinical benefit.
The necessary duration of treatment for PD in patients responding to XANAX is unknown. After a period of extended freedom from panic attacks, a carefully supervised tapered discontinuation may be attempted, but there is evidence that this may often be difficult to accomplish without recurrence of symptoms and/or the manifestation of withdrawal phenomena [see Dosage and Administration (2.3)].
2.3 Discontinuation or Dosage Reduction of XANAX
Reduced the dosage by no more than 0.5 mg every 3 days. Some patients may benefit from an even more gradual discontinuation. Some patients may prove resistant to all discontinuation regimens.
In a controlled postmarketing discontinuation study of panic disorder patients which compared the recommended taper schedule with a slower taper schedule, no difference was observed between the groups in the proportion of patients who tapered to zero dose; however, the slower schedule was associated with a reduction in symptoms associated with a withdrawal syndrome.
2.4 Dosage Recommendations in Geriatric Patients
In geriatric patients, the recommended starting oral dosage of XANAX is 0.25 mg, given 2 or 3 times daily. This may be gradually increased if needed and tolerated. Geriatric patients may be especially sensitive to the effects of benzodiazepines. If adverse reactions occur at the recommended starting dosage, the dosage may be reduced [see Use in Specific Populations (8.5), Clinical Pharmacology (12.3)].
2.5 Dosage Recommendations in Patients with Hepatic Impairment
In patients with hepatic impairment, the recommended starting oral dosage of XANAX is 0.25 mg, given 2 or 3 times daily. This may be gradually increased if needed and tolerated. If adverse reactions occur at the recommended starting dose, the dosage may be reduced [see Use in Specific Populations (8.6), Clinical Pharmacology (12.3)].
2.6 Dosage Modifications for Drug Interactions
XANAX should be reduced to half of the recommended dosage when a patient is started on ritonavir and XANAX together, or when ritonavir administered to a patient treated with XANAX. Increase the XANAX dosage to the target dose after 10 to 14 days of dosing ritonavir and XANAX together. It is not necessary to reduce XANAX dose in patients who have been taking ritonavir for more than 10 to 14 days.